Herbicidal use and compositions of halophenoxy benzamides

ABSTRACT

2-Nitro-5-(halophenoxy)benzoic acids and esters, salts, amides, and acyl halides thereof comprise a class of compounds that are highly effective pre- and post-emergence herbicides.

Waited States Patent [1 1 Theisseri Mar. 25, 1975 HERBICIDAL USE AND COMPOSITION OF HALOPHENOXY BENZAMIDES [75] Inventor: Robert J. Theissen, Westfield, N .J.

[73] Assignee: Mobil Oil Corporation, New York,

[22] Filed: Sept. 12, 1973 [21] Appl. No.: 396,976

Related U.S. Application Data [60] Continuation-in-part of Ser. No. 194,479, Nov. 1, 1971, Pat. No. 3,776,715, which is a division of Ser. No. 819,412, April 25, 1969, Pat. No. 3,652,645.

[52] US. Cl. 71/118 [51] Int. Cl A01n 9/20 [58] Field of Search 71/118, 124

[56] References Cited UNITED STATES PATENTS 3,169,849 2/1964 Jemin 71/107 3,423,470 H1969 Rohr et a 71/124 3,776,961 12/1973 Theissen 71/124 3,798,276 3/1974 Boyer 7l/124 Primary Examiner-James 0. Thomas, Jr. Attorney, Agent, or Firm-Charles A. Huggett; Hastings S. Trigg [57] ABSTRACT 2-Nitro-5-(halophenoxy)benzoic acids and esters,

salts, amides, and acyl halides thereof comprise a class of compounds that are highly effective preand postemergence herbicides.

14 Claims, No Drawings HERBICIDAL USE AND COMPOSITION OF HALOPHENOXY BENZAMIDES CROSS-REFERENCES TO RELATED APPLICATIONS This application is a continuation-in-part of copending application Ser. No. 194,479, filed Nov. 1, 1971, now U.S. Pat. No. 3,776,715, which is a division of application Ser. No. 819,412, filed Apr. 25, 1969, now U.S. Pat. No. 3,652,645.

BACKGROUND OF THE INVENTION SUMMARY OF THE INVENTION This invention provides the method for controlling plant growth that comprises applying an herbicidal amount of an herbicidal compound having the formula:

wherein X is halogen n is l to 5, and R is amido, alkylamido (C C preferably C -C or dialkylamido (C -C preferably C -C and herbicidal composition containing said compound.

DESCRIPTION OF SPECIFIC EMBODIMENTS The compounds of this invention are readily prepared by the Ullmann ether synthesis reaction between the alkali metal (Na, K) salt of a halophenol and a halo (Cl, Br)-2-nitrobenzoic acid or an ester, amide, or salt thereof. The 5-halo-2-nitrobenzoic acid is readily prepared by nitrating a m-halotoluene, followed by oxidation of the methyl group by well-known procedures.

Non-limiting examples of the compounds of this invention are:

2-nitro-5-(2',4',6-trichlorophenoxy)benzoic acid; methyl 2-nitro-5-(2',4,6'-trichlorophenoxy)benzoate; propyl 2-nitro-5-(2 ,4 ,6'-trichlorophenoxy)benzoate;

2-nitro-5-(2,4,6'-triiodophenoxy)benzoic acid;

2-nitro-5-(2',4,6'-trichlorophenoxy)benzoyl chloride;

2-nitro-5-(2,4,6-trichlorophenoxy)benzamide;

N-ethyl 2-nitro-5-(2,4,6-trichlorophenoxy)benzamide;

N-isopropyl 2-nitro-5-(2,4,6-trichlorophenoxy)benzamide;

N,N-dimethyl 2-nitro-5-(2,4,6-trichlorophenoxy)- benzamide; sodium (or potassium) 2-nitro-5(2',4',6'-

trichlorophenoxy)-benzoate;

2 ethylammonium 2-nitro-5-(2',4,6-trichlorophenoxy)- benzoate; ethanolammonium trichlorophenoxy)benzoate; sodium 2-nitro-5-(2,4',6'-trichlorophenoxy)benzoate; methyl 2-nitro-5-(2',4,5-trichlorophenoxy)benzoatc; methyl 2-nitro-5-(2',4-dichlorophenoxy)benzoate;

and methyl 2-nitro-5(2,3,4,5',6'- pentachlorophenoxy)benzoate.

The following example illustrates the preparation of a typical compound of this invention and demonstrates a method for product recovery.

EXAMPLE 1 Methyl 2-nitro-5-(2,4',6-trichlorophenoxy)benzoate A stirred solution of methyl 5-chloro-2-nitro benzoate (17.0 g., 0.079 mole) and the potassium salt of 2,4,6-trichlorophenol (18.6 g., 0.079 mole) in dimethyl sulfoxide (100 ml.) was heated at for 17 hours. The cooled reaction mixture was diluted with water (500 ml.) and then extracted with ether (3 X ml.). The combined ether fractions were washed with 10% sodium hydroxide solution (2 X 30 ml.) and then with a saturated aqueous sodium chloride solution. The ether solution was dried (Na SO and the solvent evaporated to give a dark oil. Two crystallizations (petroleum ether) gave 1.91 g. ofa pale yellow solid, m.p. 101103.

Example 1 LR. (nujol): c o I723, co 1240, and 1260 cm NMR (CDC1 methyl 3.91 ppm (3H), quartet 6.96 ppm (1H, J 2.5 and 8 c.p.s.), doublet 7.5 ppm (1H, J= 2.5 c.p.s.), broad singlet 7.05 ppm (2H), and doublet 8.01 ppm (1H, J 8

c.p.s.).

EXAMPLES 2 THROUGH 13 The ester of Example 1 was hydrolyzed to the corresponding acid and using known procedures for the preparation of amides, twelve other compounds within the scope of this invention were prepared. These compounds are:

2. 2-nitro-5-(2',4-dichlorophenoxy)benzamide.

3. N-methyl 2-nitro-5-(2,4'-dichlorophenoxy)benzamide.

4. N,N-dimethyl 2-nitro-5-(2',4-dichlorophenoxy)- benzamide.

5. N-propyl 2-nitro-5(2',4'-dichlorophenoxy)benzamide.

6. 2-nitro-5-(2',4',6-trichlorophenoxy)benzamide.

7. N-methyl 2-nitro-5-(2,4,6-trichlorophenoxy(benla i ude 8. N,N-dimethyl trichlorophenoxy)benzamide.

9. N-propyl 2-nitro-5-(2.4-6'-trichlorophenoxy)bengg H V.

10. N-isopropyl 2-nitro-5-(2',4,6'-trichlorophenoxy)- benzamide.

l1. N,N-diethyl 2-nitro-5-(2,4,6-trichlorophenoxy)- benzamide.

l2. N.N-dimethyl 2-nitro-5-(2',4-dichloro-6'- fluorophenoxy)benzamide.

13. N-secbutyl 2-nitro-5-(2',4'-dichloro-6- fluorophenoxy)benzamicle.

For comparison, the following position isomer of Example 4 was prepared, the acid of which is disclosed in U.S. Pat. No. 3,475,427.

14. N,N-dimethyl-2-nitro-3-(2',4-dichlorophenoxy)- benzamide.

The compounds of this invention can be applied in various ways to achieve herbicidal action. They can be applied, per se, as solids or in vaporized form, but are preferably applied as the toxic components in pesticidal compositions of the compounds and a carrier. The compositions can be applied, as dusts; as liquid sprays, or as gas-propelled sprays and can contain, in addition to a carrier, additives such as emulsifying agents, binding agents, gases compressed to the liquid state, odorants, stabilizers, and the like. A wide variety of liquid and solid carriers can be used. Non-limiting examples of solid carriers include talc, bentonite, diatomaceous earth, pyrophyllite, fullers earth, gypsum, flours derived from cotton seeds and nut shells, and various natural and synthetic clays having a pH not exceeding about 9.5. Non-limiting examples of liquid carriers, include water; organic solvents, such as alcohols, ketones, amides and esters; mineral oils, such as kerosene, light oils, and medium oils and vegetable oils, such as cottonseed oil.

In practice, herbicidal application is measured in terms of pounds of herbicide applied per acre. The compounds of this invention are effective herbicides when applied in herbicidal amounts, i.e., at rates be- 3 tween about 0.2 pounds and about pounds per acre.

All crop and weed species are planted individually in 3 inch plastic pots containing potting soil. Four seeds of each of corn, cotton, and snapbeans are seeded to a depth equal to the diameter of the seed. All other species are surface seeded and sprinkled with screened soil in an amount sufficient to cover the seeds. Immediately after planting, all pots are watered by sub-irrigation in greenhouse trays. Pots for the pro-emergence phase are seeded one day before treatment.

Planting dates for the post-emergence phase are varied so that all the seedlings will reach the desired stage of development simultaneously. The proper stage of seedling development for treatment in the postemergence phase is as follows:

mg point at primary leaf node.

METHOD OF TREATMENT Spray applications are made in a hood containing a movable belt and fixed spray nozzle. For passage through the spray hood, one pot of each species (preemergence phase) is placed on the forward half of a.

wooden flat and one pot of established plants (postemergence phase) is placed on the rear half of the flat. Treatments are moved to the greenhouse after spraying. Watering during the observation period is applied only by sub-irrigation.

Compounds are screened initially at a rate of application equivalent to 4 to 8 pounds per acre. Two weeks HERBICIDAI- EFFhQTIVhNE-SS atter treatment the pre and post-emergence per cent Method Propagating TN Spud Injury 18 visually rated. Subsequent testing was earned out at 2.1 and 0.5 pounds per acre. $l'zillbgflilgfixl I pifil riu mnguinuIii Herbicidal testing of the compounds of Examples 2 L K ill 'I'i.'.\' t juhiison grass 5 .s'ini'iiiil liiiiiJim through 13 and of the comparatlve compound showed g y s I livllillw'lllwl 'nk'ulli the results set forth in Table l. The plants are tabulated marant pigu'eet rillltlltlllI/IIMl'tIIQ/YUXILY Turnip Urmim m using the following abbreviations. Cotton Guswypium liirxulum var. DPL

smooth 51f Crabgrass CG Pigweed PW Com Zea Mays var. Golden Bantam Turnip TP B an Plzascolus vulguris var. Johnson grass JG Cotton CT m valentine Barnyard grass BG Corn CN Bean BN Table l Pre-lPost-Emergence Compound Dosage Example No. Lbs/Acre CG JG BG PW TP CT CN BN 4 f -/t()() /s() 2 a am 400 k 7 g ll0/70 11/24) 50/40 zlv mo loo/20 0/20 0/100 70 8 8 70/60 20/30 40/30 -/l00 80/100 50/70 0/30 50 100 9 2 30/60 0/20 0/ 20 0/91 1 30/ 30 0/0 (ll 100 0/30 l0 8 40/50 0/2 20/30 70/80 50/0 0/70 O/90 l l 8 30/40 0/ 20/100 /30 0/50 12 8 100/0 20/- 100/80 100/50 4 0/ 0/ 0/ 100/ 100/ 70/ 2 70/- 40/ 30/ 60/ 30/20 20/ l3 8 90/0 0/ 0/ 100/90 100/100 4 80/- 0/ 0/ 40/ 2 30/ 0/ 0/ 80/ 30/ 80/ l4 8 40/0 0/ 0/- 20/* 20/20 0/0 0/ 0/0 Bindweutl compound having the formula:

COR

wherein X is halogen, n is 1 to 5, and R is amido, alkylamido (C C or dialkylamido (C C 2. The method ofclaim 1, wherein said compound is N-methyl 2-nitro-5-(2,4'-dichlorophenoxy)benzumide.

3. The method ofclaim I, wherein said compound is N,N-dimethyl 2-nitro-5-(2 ,4'-dichlorophenoxy)benzamide.

4. The method of claim 1, wherein said compound is N,N-dimethyl 2-nitro-5-(2,4,6-trichlorophenoxy(- benzamide.

5. The method of claim ll, wherein said compound is N,N-dimethyl 2-nitro-5-(2,4'-dichloro-6- fluorophenoxy)benzamide.

6. The method of claim 1, wherein said compound is N-sec-butyl 2-nitro-5-(2,4-dichloro-6-fluorophenoxy)benzamide.

7. The method of claim 1, wherein said compound is 2-nitro-5-(2,4,6-trichlorophenoxy)benzamide.

8. An herbicidal composition comprising a carrier for an herbicide and an herbicidal amount of an herbicidal compound having the formula:

COR

wherein X is halogen, n is l to 5, and R is amido, alkylamido (C -C or dialkylamido (C C 9. The composition of claim 8, wherein said compound is N-methyl 2-nitro-5-(2',4'-dichlorophenoxy) benzamide.

10. The composition of claim 8, wherein said compound is N,N-dimethyl 2-nitro-5-(2',4'- dichlorophenoxy)benzamide.

ll. The composition of claim 8. wherein said compound is N, N-dimethyl 2-nitro-5-(2,4,6'- trichlorophcnoxy)benzamide 12. The composition of claim 8, wherein said compound is N,N-dimethyl 2-nitro-5(2,4-dichloro-6'- fluorophenoxy)benzamide.

13. The composition of claim 8, wherein said compound is N-sec-butyl 2-nitro-5-(2,4-dichloro-6- fluorophenoxy)benzamide.

14. The composition of claim 8, wherein said compound is 2-nitro-5-(2,4,6'-trichlorophenoxy)benza-, mide.

Disclaimer 3,873,3O3.R0bert J. Theissen, Westfield, NJ. HERBICIDAL USE AND COM- POSITION OF HALOPHENOXY BENZAMIDES. Patent dated Mar. 25, 1975. Disclaimer filed Oct. 17, 1988. by the assignee, Rhone- Poulenc Agrochimz'e.

Hereby enters this disclaimer to claims 1, 2, 3, 5, 6, 8, 9, 10, 12, and 13 of said patent.

[Official Gazette April 18, 1989.] 

1. THE METHOD FOR CONTROLLING PLANT GROWTH THAT COMPRISES APPLYING AN HERBICIDAL AMOUNT OF AN HERBICIDAL COMPOUND HAVING THE FORMULA:
 2. The method of claim 1, wherein said compound is N-methyl 2-nitro-5-(2'',4''-dichlorophenoxy)benzamide.
 3. The method of claim 1, wherein said compound is N,N-dimethyl 2-nitro-5-(2'',4''-dichlorophenoxy)benzamide.
 4. The method of claim 1, wherein said compound is N,N-dimethyl 2-nitro-5-(2'',4'',6''-trichlorophenoxy(benzamide.
 5. The method of claim 1, wherein said compound is N,N-dimethyl 2-nitro-5-(2'',4''-dichloro-6''-fluorophenoxy)benzamide.
 6. The method of claim 1, wherein said compound is N-sec-butyl 2-nitro-5-(2'',4''-dichloro-6''-fluorophenoxy)benzamide.
 7. The method of claim 1, wherein said compound is 2-nitro-5-(2'',4'',6''-trichlorophenoxy)benzamide.
 8. An herbicidal composition comprising a carrier for an herbicide and an herbicidal amount of an herbicidal compound having the formula:
 9. The composition of claim 8, wherein said compound is N-methyl 2-nitro-5-(2'',4''-dichlorophenoxy)benzamide.
 10. The composition of claim 8, wherein said compound is N,N-dimethyl 2-nitro-5-(2'',4''-dichlorophenoxy)benzamide.
 11. The composition of claim 8, wherein said compound is N, N-dimethyl 2-nitro-5-(2'',4'',6''-trichlorophenoxy)benzamide
 12. The composition of claim 8, wherein said compound is N,N-dimethyl 2-nitro-5-(2'',4''-dichloro-6''-fluorophenoxy)benzamide.
 13. The composition of claim 8, wherein said compound is N-sec-butyl 2-nitro-5-(2'',4''-dichloro-6''-fluorophenoxy)benzamide.
 14. The composition of claim 8, wherein said compound is 2-nitro-5-(2'',4'',6''-trichlorophenoxy)benzamide. 